Conventionally, for the sake of decorating a transfer image-receiving article (imparting a design property to the transfer image-receiving article), some attempts have been made, where a decorative seal having a seal base material and an thermally transferred image formed on the seal base material is used, and the seal base material provided with the thermally transferred image thus formed is stuck on the transfer image-receiving article. As the decorative seal, for example, a product where an adhesive layer, and a base material layer on which a thermally transferred image is formed (the base material layer is also referred to as “decorative layer” or the like, in some cases.) are layered in this order on a release sheet (the release sheet is also referred to as “peel-off sheet”, “releasing material”, or the like), the thus layered adhesive layer and the base material layer constituting a seal base material, has been proposed. When using the product, the seal base material is peeled off from the release sheet, then the adhesive layer is applied on the transfer image-receiving article, and thereby, the seal base material is allowed to be stuck on the transfer image-receiving article.
As the transfer image-receiving article to which the seal base material is affixed, for instance, the ones that have an individual curved surface, such as, human body, beverage containers, etc, are considered, in addition to the others that have an individual flat surface, such as a card, etc. For example, Patent Literature 1 has proposed a decorative seal for decorating an transfer image-receiving article that has a flat surface as the surface to which the seal base material is affixed, such as a message card, etc., while Patent Literature 2 has proposed another decorative seal for decorating an transfer image-receiving article that has a curvature, such as a nail, etc.
In order to sufficiently enhance the decorativeness of the transfer image-receiving material, it is necessary to stick the seal base material, on which the thermal transfer image has been formed, on the transfer image-receiving material without causing crinkle or the like. However, when using a material having a curvature as the transfer image-receiving material, it is difficult to stick the seal base material on the transfer image-receiving material without crinkle, and there is a room for improvement in this point with respect to the decorative seal which has been proposed up to now.
Recently, it has been widely practiced to form a thermal transfer image by using a sublimation type thermal transfer system that is excellent in halftone reproducibility and gradation, and that can clearly develop a full color image as the original. In forming a thermal transfer image on the decorative seal, it is important that the preservability of the formed thermal transfer image is high, in other words, it is important that the formed thermal transfer image does not fade or is difficult to discolor. Under the current circumstances, however, these aspects have not been studied enough.